71388631 has 2 divisors, whose sum is σ = 71388632. Its totient is φ = 71388630.

The previous prime is 71388613. The next prime is 71388673. The reversal of 71388631 is 13688317.

Together with previous prime (71388613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is an emirp because it is prime and its reverse (13688317) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71388631 - 2⁵ = 71388599 is a prime.

It is a super-2 number, since 2×71388631² = 10192673272108322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71388431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35694315 + 35694316.

It is an arithmetic number, because the mean of its divisors is an integer number (35694316).

Almost surely, 2^71388631 is an apocalyptic number.

71388631 is a deficient number, since it is larger than the sum of its proper divisors (1).

71388631 is an equidigital number, since it uses as much as digits as its factorization.

71388631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 37.

The square root of 71388631 is about 8449.1793092584. The cubic root of 71388631 is about 414.8359171337.

The spelling of 71388631 in words is "seventy-one million, three hundred eighty-eight thousand, six hundred thirty-one".